"Two women linked by a common killer," Albany County prosecutor Steven Sharp told a jury as Mero sat in the defendant's chair in Albany County Court during opening statements in his trial on two counts of second-degree murder.

"These were not murders committed in broad daylight," Sharp told the jury after outlining his case. "These murders were committed in secret; the bodies of Megan and Shelby were disposed of in a way to keep them secret."

Mero, 29, worked for the Albany Water Department when Countermine's remains were found in May 2015 by a jogger on land owned by the Water Department in Coeymans. Countermine, 23, was last seen on Dec. 3, 2014.

Cunningham was found dead after a Jan. 27, 2013, fire at the apartment she shared with Mero at 12 Arcadia Ave. in Albany. Investigators took a second look at Cunningham's death after the discovery of Countermine's body.

If convicted of either murder, Mero would face up to 25 years to life in state prison.

Mero defense attorney Cheryl Coleman, however, told the jury in her opening statement that the evidence in Cunningham's case points to an accidental death, and in Countermine's case, Coleman questioned the timeline of the alleged killing: Though Countermine was with Mero the day she was reported missing, there were sightings of her later, Coleman said.

She also pointed to other possible suspects in Countermine's murder.

"They want you to buy into the circular argument," Coleman said. "They want you to believe that he did one (murder) because they want you to believe that he did the other."

Sharp contended that no soot was found in Cunningham's lungs, suggesting she died before the fire. He also said a neighbor heard an argument that night between a man and a woman.

Mero said he left before the fire started and last saw Cunningham passed out and helped her to her bedroom, Sharp said.

Mero then left for 2.5 hours, the time during which the fire happened, Sharp said. Coleman argued that experts will discount that time frame and cite super-heated air as the cause of death and as the reason no soot was found in her lungs.

Fire department and forensic experts, Coleman said, won't change their original accidental assessment of the fire. The insurance company didn't even challenge it, Coleman said. Tests also showed Cunningham was intoxicated and had marijuana in her system at the time of her death, just as Mero said.

Mero met Countermine through an online ad for prostitution, Sharp said. She was addicted to heroin and prostituted herself to support that addiction.

She had met with Mero before and always left information behind about who she was meeting for sex. She disappeared after visiting Mero for what was to be a $500 multi-hour visit, Sharp said.

Despite her addiction, she contacted her father almost daily. Those contacts stopped the day she disappeared, Sharp said. Her father even used the information she left behind to contact Mero and demand answers, Sharp said.

Mero admitted that Countermine had been with him. He told her father she did heroin that day, and that he kicked her out because of that. The father even hired private investigators, Sharp said.

Coleman suggested there are other suspects and reasons for Countermine's disappearance. The land in Coeymans is accessible to many, she said.